cc: Add DEFINE_ENUM macro.

cc/resources/managed_tile_state.cc

Index: cc/resources/managed_tile_state.cc
diff --git a/cc/resources/managed_tile_state.cc b/cc/resources/managed_tile_state.cc
index cf4a7a7b869520b40757bca3873eb16c2702c75e..89fd59b225f34ea6b21b12b69dd5a4f530eaefc9 100644
--- a/cc/resources/managed_tile_state.cc
+++ b/cc/resources/managed_tile_state.cc
@@ -33,11 +33,10 @@ scoped_ptr<base::Value> ManagedTileBinAsValue(ManagedTileBin bin) {
   case NEVER_BIN:
       return scoped_ptr<base::Value>(base::Value::CreateStringValue(
           "NEVER_BIN"));
-  default:
-      DCHECK(false) << "Unrecognized ManagedTileBin value " << bin;
-      return scoped_ptr<base::Value>(base::Value::CreateStringValue(
-          "<unknown ManagedTileBin value>"));
   }
+  DCHECK(false) << "Unrecognized ManagedTileBin value " << bin;
+  return scoped_ptr<base::Value>(base::Value::CreateStringValue(
+      "<unknown ManagedTileBin value>"));
 }
 
 scoped_ptr<base::Value> ManagedTileBinPriorityAsValue(
@@ -49,11 +48,10 @@ scoped_ptr<base::Value> ManagedTileBinPriorityAsValue(
   case LOW_PRIORITY_BIN:
       return scoped_ptr<base::Value>(base::Value::CreateStringValue(
           "LOW_PRIORITY_BIN"));
-  default:
-      DCHECK(false) << "Unrecognized ManagedTileBinPriority value";
-      return scoped_ptr<base::Value>(base::Value::CreateStringValue(
-          "<unknown ManagedTileBinPriority value>"));
   }
+  DCHECK(false) << "Unrecognized ManagedTileBinPriority value";
+  return scoped_ptr<base::Value>(base::Value::CreateStringValue(
+      "<unknown ManagedTileBinPriority value>"));
 }
 
 ManagedTileState::ManagedTileState()
@@ -65,10 +63,10 @@ ManagedTileState::ManagedTileState()
       distance_to_visible_in_pixels(std::numeric_limits<float>::infinity()),
       visible_and_ready_to_draw(false),
       scheduled_priority(0) {
-  for (int i = 0; i < NUM_TREES; ++i) {
-    tree_bin[i] = NEVER_BIN;
+  for (int i = 0; i < ManagedTileBinPriority_ARRAYSIZE; ++i)
     bin[i] = NEVER_BIN;
-  }
+  for (int i = 0; i < WhichTree_ARRAYSIZE; ++i)
+    tree_bin[i] = NEVER_BIN;
 }
 
 ManagedTileState::TileVersion::TileVersion()